app: detect CLI availability and add command palette copy action

crates/yaak-common/src/command.rs

@@ -1,4 +1,6 @@
-use std::ffi::OsStr;
+use std::ffi::{OsStr, OsString};
+use std::io::{self, ErrorKind};
+use std::process::Stdio;
 
 #[cfg(target_os = "windows")]
 const CREATE_NO_WINDOW: u32 = 0x0800_0000;
@@ -14,3 +16,27 @@ pub fn new_xplatform_command<S: AsRef<OsStr>>(program: S) -> tokio::process::Com
     }
     cmd
 }
+
+/// Creates a command only if the binary exists and can be invoked with the given probe argument.
+pub async fn new_checked_command<S: AsRef<OsStr>>(
+    program: S,
+    probe_arg: &str,
+) -> io::Result<tokio::process::Command> {
+    let program: OsString = program.as_ref().to_os_string();
+
+    let mut probe = new_xplatform_command(&program);
+    probe.arg(probe_arg).stdin(Stdio::null()).stdout(Stdio::null()).stderr(Stdio::null());
+
+    let status = probe.status().await?;
+    if !status.success() {
+        return Err(io::Error::new(
+            ErrorKind::NotFound,
+            format!(
+                "'{}' is not available on PATH or failed to execute",
+                program.to_string_lossy()
+            ),
+        ));
+    }
+
+    Ok(new_xplatform_command(&program))
+}